Chemistry of the Atmosphere: Atmospheric Pollutants

Question 1

What is released when fossil fuels are completely combusted? What does this contribute towards?

Answer 1

Carbon dioxide and water vapour which are both greenhouse gasses. This contributes to climate change.

Question 2

What is produced if a fuel is burned in incomplete combustion?

Answer 2

• particulates
• carbon monoxide
• carbon dioxide

Question 3

What is the issue with carbon monoxide?

Answer 3

• toxic gas to humans
• colourless and odourless

Question 4

How is carbon monoxide toxic to humans?

Answer 4

• binds to haemoglobin
• haemoglobin cannot carry as much oxygen
• less oxygen is able to be transported round the body
• a lack of oxygen in the blood can lead to fainting, a coma or even death

Question 5

How is sulphur dioxide released into the atmosphere?

Answer 5

• some fuels, like coal, contain sulfur
• when these are burned, the sulfur is oxidised
• this produces the gas SO₂

Question 6

How are oxides of nitrogen produced?

Answer 6

• produced inside engines, eg cars
• the high temperatures found here cause nitrogen and oxygen from the air to react

Question 7

What effect does sulphur dioxide and oxides of nitrogen have on humans?

Answer 7

They cause respiratory problems in humans.

Question 8

What effect does sulphur dioxide and oxides of nitrogen have on the environment?

Answer 8

They dissolve in rain water to form acid rain.
This can damage trees and corrode buildings made from limestone.

Question 9

What are particulates?

Answer 9

• particles of carbon (soot)
• unburned hydrocarbons

Question 10

How do particulates impact human health?

Answer 10

• increase the risk of heart disease and lung disease

Question 11

How do particulates impact the environment?

Answer 11

• cause global dimming by reducing the amount of sun that reaches the earth’s surface
• global dimming could be affecting rainfall patterns

Question 12

How are particulates released into the atmosphere?

Answer 12

Incomplete combustion of fuels.

Question 13

What are the advantages of complete combustion?

Answer 13

• less soot (carbon particulates) is made with complete combustion
• more heat per gram of fuel is released with complete combustion
• poisonous carbon monoxide is not produced with complete combustion

Question 14

What are the effects of acid rain?

Answer 14

• damages certain buildings and statues
• corrodes metals
• damages plants by falling on them or making soil more acidic than they can grow in